Influence of aging on murine neutrophil and macrophage function against Candida albicans

Previous work by our group showed that aged C57BL/6 mice develop an altered innate and adaptive immune response to Candida albicans and are more susceptible to systemic primary candidiasis. In this work, we used young (2-3 months old) and aged (18-20 months old) C57BL/6 mice to study in vitro the influence of aging on (1) the fungicidal activity of neutrophils and macrophages, (2) the production of cytokines by resident peritoneal macrophages in response to C. albicans, and (3) cell surface Toll-like receptor (TLR) 2 expression on resident peritoneal macrophages. Our results indicate that murine phagocytes have a fungicidal activity well preserved with aging. In vitro production of proinflammatory cytokines (IL-6, IL-1beta, and tumor necrosis factor-alpha and chemokines (MIP-2) by purified (CD11b(+)) peritoneal macrophages in response to yeasts and hyphae of C. albicans was significantly lower in aged mice as compared with young mice. However, the production of IL-10 by macrophages, in response to C. albicans, was similar in both young and aged animals. Moreover, baseline TLR2 surface expression level was lower on aged macrophages than on control macrophages. Taken together, these data indicate that the increased susceptibility to C. albicans disseminated infections in aged mice is correlated with defects in TLR2 expression and in cytokine production, but not with an impaired fungicidal activity.     

Induction of mixed-function oxygenase system and antioxidant enzymes in the coral Montastraea faveolata on acute exposure to benzo(a)pyrene

Components of the cytochrome P(450) monooxygenase system (MFO) and antioxidant enzymes were investigated in the coral Montastraea faveolata exposed to the organic contaminant benzo(a)pyrene (B(a)P). For bioassays the corals were exposed to increasing concentrations of B(a)P (0.01 and 0.1 ppm) for 24 and 72 h, with water renewal every 24 h. Enzymatic activity of catalase (CAT), superoxide dismutase (SOD) and glutathione S-transferase (GST) were measured in host (polyp) and hosted (zooxanthellae) cells. NADPH cytochrome c reductase activity and contents of cytochrome P(450) and P(420) were only measured in the polyp. Antioxidant enzymes CAT and SOD in polyps and zooxanthellae and GST in polyps increased significantly at the highest concentration and maximum time of exposure. Cytochrome P(420) was found in all colonies, and the cytochrome P(450) content was greatest in the colonies from the highest concentrations of contaminant. NADPH cytochrome c reductase activity and the concentration of pigments did not vary between treatments. This is the first report of the induction of both detoxifying mechanisms, the MFO system and antioxidant enzymes on acute exposure to an organic contaminant in the reef-constructing coral species M. faveolata.     

Insight into the role of CYBA A640G and C242T gene variants and coronary heart disease risk. A case-control study

The CYBA gene variants have been inconsistently associated with coronary heart disease (CHD) risk. A case-control study was conducted genotyping 619 subjects to explore the contribution of C242T and A640G to CHD risk in the population. A significant risk was found associated with GG homozygosity (odds ratio (OR) 2.132, 95% confidence interval, 1.113-4.085). The C242T variant was associated with CHD risk in women. Bias due to population stratification was analysed. Phenotype changes linked to these polymorphisms were evaluated. Superoxide measurements revealed higher production as indicated by the presence of the G and T alleles. Differences in mRNA concentration in heterozygous A640G samples were analysed. Higher levels of G allele mRNA compared with A allele mRNA were found. NAD(P)H oxidase p22phox sub-unit expression was evaluated with Western blot. Experiments revealed a gradual relationship in p22phox protein expression according to genotypes of the analysed variants. Those GG TT double homozygous showed increased p22phox protein expressions regarding AA CC double homozygous. This study has demonstrated increased expression and activity of the NAD(P)H system components during atherogenesis and the results could help explain the relevance of the A640G variant as a CHD marker.     

Response of cytokinin pool and cytokinin oxidase/dehydrogenase activity to abscisic acid exhibits organ specificity in peas

Changes in cytokinin pool and cytokinin oxidase/dehydrogenase activity (CKX EC: 1.5.99.12) in response to increasing abscisic acid (ABA) concentrations (0.5–10 μM) were assessed in the last fully expanded leaves and secondary roots of two pea (Pisum sativum) varieties with different vegetation periods. Certain organ diversity in CKX response to exogenous ABA was observed. Treatment provoked altered cytokinin pool in the aboveground parts of both studied cultivars. Specific CKX activity was influenced significantly basically in roots of the treated plants. Results suggest that ABA-mediated cytokinin pool changes are leaf-specific and involve certain root signals in which CKX activity presents an important link. This enzymatic activity most probably regulates vascular transport of active cytokinins from roots to shoots.     

Mexican Arnica Anti–Inflammatory Action: Plant Age is Correlated with the Concentration of Anti–Inflammatory Sesquiterpenes in the Medicinal Plant <Emphasis Type="Italic">Heterotheca inuloides</Emphasis> Cass. (Asteraceae)<Superscript>1</Superscript>

Mexican Arnica Anti–Inflammatory Action: Plant Age Is Correlated with the Concentration of Anti–inflammatory Sesquiterpenes in the Medicinal Plant Heterotheca inuloides Cass. (Asteraceae). Mexican árnica (Heterotheca inuloides Cass.) is a widely used anti–inflammatory medicinal plant in Mexican folk medicine. Although it has been suggested that plant age, fertilization, and harvesting regime influence the concentration of secondary compounds affecting the therapeutic activity of the plant, the effect of these variables on the concentration of the Mexican árnica anti–inflammatory compounds was not known. We quantified anti–inflammatory sesquiterpenes (caryolan–1, 9β–diol, cadalen–15–oic acid, 7–hydroxycadalene, 4–hydroxy–2–isopropyl–4, 7–dimethyl–1[4H] naftalinone, 7–hydroxy–4αH–3, 4–dihydrocadalene, β–caryophyllene, and β–caryophyllene epoxide) in Mexican árnica plants subjected to fertilization and successive harvests of flowering stems, conditions that mimic the cultivation and harvesting for árnica in México. Fertilization and successive harvesting and their interaction had no significant effect on the concentration of anti–inflammatory compounds. However, the concentrations of these compounds were 60% higher in flowering stems from 15–month–old plants than in those from 4– or 8–month–old plants and was independent of the number of harvests and fertilization regime applied.     

ARABIDOPSIS THALIANA HOMEOBOX GENE1 establishes the basal boundaries of shoot organs and controls stem growth

Apical meristems play a central role in plant development. Self-renewing cells in the central region of the shoot meristem replenish the cell population in the peripheral region, where organ primordia emerge in a predictable pattern, and in the underlying rib meristem, where new stem tissue is formed. While much is known about how organ primordia are initiated and their lateral boundaries established, development at the interface between the stem and the meristem or the lateral organs is poorly understood. Here, we show that the BELL-type ARABIDOPSIS THALIANA HOMEOBOX GENE1 (ATH1) is required for proper development of the boundary between the stem and both vegetative and reproductive organs and that this role partially overlaps with that of CUP-SHAPED COTYLEDON genes. During the vegetative phase, ATH1 also functions redundantly with light-activated genes to inhibit growth of the region below the shoot meristem. Consistent with a role in inhibiting stem growth, ATH1 is downregulated at the start of inflorescence development and ectopic ATH1 expression prevents growth of the inflorescence stem by reducing cell proliferation. Thus, ATH1 modulates growth at the interface between the stem, meristem, and organ primordia and contributes to the compressed vegetative habit of Arabidopsis thaliana.     

Genetic parameters for body weight, carcass chemical composition and yield in a broiler-layer cross developed for QTL mapping

The objective of this study was to estimate genetic and phenotypic correlations of body weight at 6 weeks of age (BW6), as well as final carcass yield, and moisture, protein, fat and ash contents, using data from 3,422 F2 chickens originated from reciprocal cross between a broiler and a layer line. Variance components were estimated by the REML method, using animal models for evaluating random additive genetic and fixed contemporary group (sex, hatch and genetic group) effects. The heritability estimates (h(2)) for BW6, carcass yield and percentage of carcass moisture were 0.31 ± 0.07, 0.20 ± 0.05 and 0.33 ± 0.07, respectively. The h(2) for the percentages of protein, fat and ash on a dry matter basis were 0.48 ± 0.09, 0.55 ± 0.10 and 0.36 ± 0.08, respectively. BW6 had a positive genetic correlation with fat percentage in the carcass, but a negative one with protein and ash contents. Carcass yield, thus, appears to have only low genetic association with carcass composition traits. The genetic correlations observed between traits, measured on a dry matter basis, indicated that selection for carcass protein content may favor higher ash content and a lower percentage of carcass fat.     

Spores morphology and synangia in neotropical fern species of Marattia (Marattiaceae)

The Marattiaceae are represented by a small family of four to six genera that bear esporogenous structures of two types: sorus with free eusporangia in Angiopteris and Archangiopteris, and indurated synangium in Christensenia, Danaea and Marattia. Marattia is a pantropical genus of about eight to ten species in the paleotropic and seven to eight species in the neotropic. In order to describe the spores and sinangia morphology, this study analyzed the shape of the receptacles, and the position of the synangia, and evaluated the spores with SEM, of seven neotropical species of the genus Marattia: M. alata, M. cicutifolia, M. excavata, M. interposita, M. laevis, M. laxa y M. weinmanniifolia from several collections. The receptacles were fully developed in M. cicutifolia and M. laevis, and scarcely overelevated in the rest of the species. The synangium was ellipsoidal and had intramarginal to supramedial position in the laminae. The spores of Marattia were elliptic. Among the taxa, only monolete spores were found, with no trilete, aborted or deformed spores. The laesura was linear and reached about two of the total length of the spore. The perispore appears as a continuous thin layer deposited on the exospore according to its ornamentation in M. cicutifolia and M. laevis. It is smooth in M. alata, rugate in M. excavata and pustulate-rugate in two species: M. interposita and M. laxa. The exospore is echinate in M. cicutifolia and M. laevis and pustulate in the other species. In M. weinmannifolia spores produced by the same sinangium may have different ornamentation types. We concluded that, while the presence of ellipsoidal and superficial synangia and monolete spores aperture were generic traits, the micro and macro-ornamentation types of the perispores and exospores vary at specific level. Besides, macro-ornamentation can be bulliform (pustulate), a combination of bulliform and muriform types (pustulate-rugate), muriform (rugate-retate) and stelliform (echinate); finally, granular micro-ornamentation can be seen frecuently in perispores.     

Chestnut cultivar diversification process in the Iberian Peninsula, Canary Islands, and Azores

This is a large-scale molecular study based on simple sequence repeat (SSR) loci of the diversification process in chestnut cultivars from Portugal and Spain, from the northern Iberian Peninsula to the Canary Islands and the Azores. A total of 593 grafted chestnut trees (Castanea sativa Mill.) were analysed with 10 SSRs: 292 from Portugal and 301 from Spain. Some of the trees studied were more than 300 years old. Accessions were analysed using a model-based Bayesian procedure to assess the geographical structure and to assign individuals to reconstructed populations based on the SSR genotypes. We found 356 different genotypes with a mean value of clonality of 33% owing to grafting. Mutations accounted for 6%, with hybridization being the main diversification process that can explain the great diversity found. Ten main cultivar groups were detected: four in northern Spain, five in the centre of the Iberian Peninsula, and one in southern Spain related to the centre of the Iberian Peninsula. This work demonstrated that cultivar origin and the diversification process was a combination of clonal propagation of selected seedlings, hybridization, and mutations, which allowed high levels of diversity to be maintained with respect to selected clones for fruit production. Furthermore, seedlings and graft sticks facilitated the transport to new destinations in the colonization process, transporting sometimes more than 3000 km if we consider the Azores and the Canary Islands.